No! LM386 is noisy.LM386 link
Interesting because the outputs will drive more than +20dBu into a 600 ohm load. Are you suggesting I can use this same output to drive lower impedance headphones simply by including a suitable series resistor?12V supply sounds marginal (low) for an effective master section headphone amp. To accommodate the wide range of headphone impedances you could encounter. Good practice is generally to provide healthy signal swing to drive 600 ohm cans adequately but to also use a series resistance to current limit when driving low impedance phones.
I wouldn't normally ask because I would just use my regular tube one but in this one instance there is just no room so reluctantly I need a semiconductor answerNo! LM386 is noisy.
Ah, the old headphone amp discussion. I suppose it's about that time again.
I may well do that. I have so far come across designs using the LM386 (high distortion) and one using NE5532 with added output transistors. I was hoping this was a well trodden path and there would be well known readily available solutions. I know of a Doug Self design that uses a TL072 with a couple of output transistors, maybe that will do.I agree with JR. The trick is how to handle different impedance loads. It seems to me just putting a buildout resistor inside the feedback loop of a typical amp would be a nice, and very simple, solution for that. Impedance is kept low for all loads and yet your not going to blow out your drums by accident.
I would just make a PCB though. There's always something not to like about whatever off-the-shelf module. And it should be so small that you can get some from OSHPark for less than whatever module.
It depends very much on your intention. If you want just something that indicates there is a decent signal, it's ok, but note that modern low-Z headphones are designed to operate wit a very low source Z. Adding a resistor in series changes significantly the bass response.Are you suggesting I can use this same output to drive lower impedance headphones simply by including a suitable series resistor?
I thought (from a brief read of the datasheet) that a gain of 20 was the minimum. Can it be made less than this?It's noisy when it's used with the default gain of 20. For most modern low-Z headphones, unity gain is more than sufficient for a standard +4dBu source.
Sounds like no problemo.... The last I seriously researched headphone impedances I think I found an impedance range from as low as 3.2 ohm up to over 1k ohm... I suspect 600 ohm is a practical upper limit and maybe 8 Ohms on the low end. If you have higher end customers you can probably ASSume premium headphones (40-60 ohm). Maybe ask your customers. Adding a series resistance was common practice, not exactly audiophile.Interesting because the outputs will drive more than +20dBu into a 600 ohm load. Are you suggesting I can use this same output to drive lower impedance headphones simply by including a suitable series resistor?
Interesting because the outputs will drive more than +20dBu into a 600 ohm load.